16801-63-1Relevant articles and documents
An alkoxyamine compound, alkoxy alcohol oxidation catalyst and method of using the alcohol oxidation
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Paragraph 0096; 0099-0100, (2017/02/02)
PROBLEM TO BE SOLVED: To provide a novel alkoxyamine compound which can be easily manufactured and applied suitably as an alcohol oxidation catalyst capable of exerting sufficiently high catalytic activity in oxidation of primary and secondary alcohols.SOLUTION: There is provided an alkoxyamine compound with a homoadamantane skeleton represented by the general formula (1) in the figure. [In the formula (1), Rand Rare each independently any one selected from the group consisting of a hydrogen atom and alkyl groups that may be substituted.
Highly efficient aerobic oxidation of alcohols by using less-hindered nitroxyl-radical/copper catalysis: Optimum catalyst combinations and their substrate scope
Sasano, Yusuke,Kogure, Naoki,Nishiyama, Tomohiro,Nagasawa, Shota,Iwabuchi, Yoshiharu
, p. 1004 - 1009 (2015/03/31)
The oxidation of alcohols into their corresponding carbonyl compounds is one of the most fundamental transformations in organic chemistry. In our recent report, 2-azaadamantane N-oxyl (AZADO)/copper catalysis promoted the highly chemoselective aerobic oxidation of unprotected amino alcohols into amino carbonyl compounds. Herein, we investigated the extension of the promising AZADO/copper-catalyzed aerobic oxidation of alcohols to other types of alcohol. During close optimization of the reaction conditions by using various alcohols, we found that the optimum combination of nitroxyl radical, copper salt, and solution concentration was dependent on the type of substrate. Various alcohols, including highly hindered and heteroatom-rich ones, were efficiently oxidized into their corresponding carbonyl compounds under mild conditions with lower amounts of the catalysts.
Mechanistic insight into aerobic alcohol oxidation using NOx-nitroxide catalysis based on catalyst structure-activity relationships
Shibuya, Masatoshi,Nagasawa, Shota,Osada, Yuji,Iwabuchi, Yoshiharu
, p. 10256 - 10268 (2015/02/19)
The mechanism of an NOx-assisted, nitroxide(nitroxyl radical)-catalyzed aerobic oxidation of alcohols was investigated using a set of sterically and electronically modified nitroxides (i.e., TEMPO, AZADO (1), 5-F-AZADO (2), 5,7-DiF-AZADO (3), 5-MeO-AZADO (4), 5,7-DiMeO-AZADO (5), oxa-AZADO (6), TsN-AZADO (7), and DiAZADO (8)). The motivation for the present study stemmed from our previous observation that the introduction of an F atom at a remote position from the nitroxyl radical moiety on the azaadamantane nucleus effectively enhanced the catalytic activity under typical NOx-mediated aerobic-oxidation conditions. The kinetic profiles of the azaadamantane-N-oxyl-[AZADO (1)-, 5-F-AZADO (2)-, and 5,7-DiF-AZADO (3)]-catalyzed aerobic oxidations were closely investigated, revealing that AZADO (1) showed a high initial reaction rate compared to 5-F-AZADO (2) and 5,7-DiF-AZADO (3); however, AZADO-catalyzed oxidation exhibited a marked slowdown, resulting in ～90% conversion, whereas 5-F-AZADO-catalyzed oxidation smoothly reached completion without a marked slowdown. The reasons for the marked slowdown and the role of the fluoro group are discussed. Oxa-AZADO (6), TsN-AZADO (7), and DiAZADO (8) were designed and synthesized to confirm their comparable catalytic efficiency to that of 5-F-AZADO (2), providing supporting evidence for the electronic effect on the catalytic efficiency of the heteroatoms under NOx-assisted aerobic-oxidation conditions.
